[gst-devel] Bug in gst_bin_set_state ?

Andreas Rottmann a.rottmann at gmx.at
Thu Jan 20 05:57:10 CET 2005


Hi!

I tried to get v4l2src to work with gstreamer, and in the process
found out that gst_v4l2src_change_state was never called when setting
the state of the pipeline. Not being knowledgeable of the gstreamer
internals, I played around a bit, and found out that calling 

    gst_element_set_state (pipeline, GST_STATE_PLAYING);

which I thought would invoke gst_v4l2src_change_state, did in fact
nothing with its children at all. So, I looked at the code and it
*appeared* to have the logics the wrong way around:

GstElementStateReturn
gst_bin_set_state (GstElement * element, GstElementState state)
{
  GstBin *bin = GST_BIN (element);

  if (GST_STATE (bin) == state) {
    ... // iterate over the kids here
  } else {
    ... // delegate call to parent
  }
}

I changed the "if (GST_STATE (bin) == state)" to "if (GST_STATE (bin)
!= state)", and voila, the v4l2src element worked nicely. Could it
really be that I've found such a fundamental bug, or am I just ways
off track here?

Patch attached.

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Regards, Rotty
-- 
Andreas Rottmann         | Rotty at ICQ      | 118634484 at ICQ | a.rottmann at gmx.at
http://yi.org/rotty      | GnuPG Key: http://yi.org/rotty/gpg.asc
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A. Because it breaks the logical sequence of discussion
Q. Why is top posting bad?


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